Conventional wireless devices are designed to work or operate in a specified frequency range or band with limited transmit power levels. Government agencies, e.g., the U.S. Federal Communications Commission (FCC), license specific bands to specific network operators. The FCC limits transmit power for each of the licensed bands to provide public safety and to reduce potential co-band and adjacent band interference levels.
Example licensed frequency bands include cellular telephony or Personal Communication Service (PCS) bands, as well as Advanced Wireless Services (AWS) bands and Global System for Mobile Communications (GSM) bands. Cellular communications in the U.S. typically operate in the frequency ranges of 824-849 MHz, and 869-894 MHz. Further bands include 700 MHz bands, such as Band 12. Broadband PCS communications in the U.S. typically operate in the frequency ranges of 1850-1910 MHz and 1930-1990 MHz, while narrowband PCS typically operates in the frequency ranges of 901-902 MHz, 930-931 MHz, and 940-941 MHz. The 4940-4990 MHz band (referred to as the 4.9 GHz licensed band) is available but is designated by the FCC for support of public safety. Other licensed bands, such as those supporting Third Generation (3G) wireless communications, include frequency bands such as 1710-1755 MHz, 2110-2155 MHz, 2305-2320 MHz, 2345-2360 MHz (Wireless Communication Services, WCS band), and 2500-2690 MHz (Multichannel Multipoint Distribution Services, MMDS band).
Licensees to a licensed band usually have an exclusive right to provide services with the band in a specified geographic area, for a defined term and within specified times. The license is exclusive in the sense that no other service providers are typically allowed to provide services in the same band, in the same area and at the same time. Other licensed bands include, but are not limited to, a licensed band identified as allocated for Worldwide Interoperability for Microwave Access (WIMAX).
Many wireless networks provide communication services to multiple types or generations of devices. For example, a cellular network may provide connectivity to second-generation (2G) cellular devices using, e.g., the GSM standard, third-generation (3G) cellular devices using, e.g., the Universal Mobile Telecommunications System (UMTS) standard, or fourth-generation (4G) cellular networks using, e.g., the Long Term Evolution (LTE) standard. Within the any particular cell of such a network, cellular devices may be operating using multiple network types or standards. Moreover, a particular cellular device may switch between network types in operation, e.g., due to a circuit-switched (CS) fallback operation when leaving LTE coverage during a call but still within GSM coverage. Each network type may operate in a separate licensed band in any given cell.